The Janesville School District will delay the start time of classes Friday morning because of subzero temperatures in the overnight forecast.
Middle and high school students should report to their schools at 10 a.m., and elementary students should report at 10:15 a.m., according to the district's website.
Morning sessions for early childhood programs and P4J, the district's 4-year-old kindergarten, are canceled at Adams, Jackson, Jefferson, Madison, Washington and Wilson elementary schools.
Afternoon sessions of those programs will go on as scheduled.
District officials recommend contacting P4J site directors for cancellations, closings or delays for all other P4J programs.